Mapeamento dos laboratórios de alevinos do estado do Rio Grande do Sul e desenvolvimento de marcadores moleculares para jundiá (Rhamdia sp.).

Abstract

Agribusiness is fundamental for the Brazilian economy and the southern region of the country has steadily been increasing in fish farming scenario. However Rio Grande do Sul (RS) does not have a survey of production data (production units fingerlings, availability and demand for fingerlings, technical assistance to producers, cultivation conditions, number and origin of the breeding of the main species of fish produced state). However, the catfish (Ramdia quelen) has been considered as promising species for production in southern Brazil, not only the productivity advantages, but also by research and experiments. A species recently adopted by the researchers, there is little information available in genetics for this species of fish. This study is based on two axes, first map producers and collect information about the production of RS and subsequently develop molecular markers for native species with the highest potential for production, catfish. At first a questionnaire consisting of open questions and closed questions of the type was developed. The questionnaire was proposed to sixteen producers of fingerlings of RS between the months of September 2011 and February 2012. The analysis shows that silver catfish fingerlings and grass carp (Ctenopharigodon idella) are the most produced by mills of visits fingerlings. It was evident also that the production of fingerlings is an important link in the production chain of fish farming in the state of RS, generating income and employment. It was found that many enterprises had failures in the management and employees in the management of water quality and reproduction, which reinforces the implementation of collaborative efforts between manufacturers, research institutions, extension and promotion, in order to disseminate among producers the importance of monitoring and control of water quality parameters; develop breeding programs, planning and management technologies that seek to reduce production costs and consider the local situation of the enterprises. In a second moment, a shotgun paired-end library was prepared from genomic DNA of catfish. The sequencing was carried out on a library HiSeq sequencer (Illumina) with paired-end reads of 100 base pairs and grouped with other species. From a single race five million readings obtained were analyzed with the program PAL_FINDER_v0.02.03. Each of the primers had loci embedding sequence M13 and a group of twelve loci and was chosen for further amplified microsatellite fragments obtained. Of all readings obtained, 6.331 microsatellite loci potentially amplifiable (PALs) were found, of which 4.755 were dinucleotide, 728 trinucleotide, 729 tetranucleotide, 117 pentanucleotídeo and 2 were hexanucleotídeo. The twelve microsatellite loci selected for amplification were sequenced. The knowledge developed microsatellite was through sequencing by the Sanger method, with fragments between 140 and 200bp. However, only six loci had satisfactory results and displayed polymorphism. However, we can define the shotgun paired-end HiSeq platform (Illumina) sequencing strategy through effective library is presented, as well as being quick and inexpensive to develop microsatellite markers for species not model like the catfish.